Fix bugs in lowering of FCOPYSIGN nodes.

- FCOPYSIGN nodes that have operands of different types were not handled.
- Different code was generated depending on the endianness of the target.

Additionally, code is added that emits INS and EXT instructions, if they are
supported by target (they are R2 instructions).

llvm-svn: 154540

1 files changed, 91 insertions, 52 deletions

diff --git a/llvm/lib/Target/Mips/MipsISelLowering.cpp b/llvm/lib/Target/Mips/MipsISelLowering.cpp
index c772c5d371c..2b3921d2b1c 100644
--- a/llvm/lib/Target/Mips/MipsISelLowering.cpp
+++ b/llvm/lib/Target/Mips/MipsISelLowering.cpp
@@ -1756,66 +1756,105 @@ SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
                       MachinePointerInfo(SV), false, false, 0);
 }
 
-// Called if the size of integer registers is large enough to hold the whole
-// floating point number.
-static SDValue LowerFCOPYSIGNLargeIntReg(SDValue Op, SelectionDAG &DAG) {
-  // FIXME: Use ext/ins instructions if target architecture is Mips32r2.
-  EVT ValTy = Op.getValueType();
-  EVT IntValTy = MVT::getIntegerVT(ValTy.getSizeInBits());
-  uint64_t Mask = (uint64_t)1 << (ValTy.getSizeInBits() - 1);
-  DebugLoc dl = Op.getDebugLoc();
-  SDValue Op0 = DAG.getNode(ISD::BITCAST, dl, IntValTy, Op.getOperand(0));
-  SDValue Op1 = DAG.getNode(ISD::BITCAST, dl, IntValTy, Op.getOperand(1));
-  SDValue And0 = DAG.getNode(ISD::AND, dl, IntValTy, Op0,
-                             DAG.getConstant(Mask - 1, IntValTy));
-  SDValue And1 = DAG.getNode(ISD::AND, dl, IntValTy, Op1,
-                             DAG.getConstant(Mask, IntValTy));
-  SDValue Result = DAG.getNode(ISD::OR, dl, IntValTy, And0, And1);
-  return DAG.getNode(ISD::BITCAST, dl, ValTy, Result);
-}
+static SDValue LowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
+  EVT TyX = Op.getOperand(0).getValueType();
+  EVT TyY = Op.getOperand(1).getValueType();
+  SDValue Const1 = DAG.getConstant(1, MVT::i32);
+  SDValue Const31 = DAG.getConstant(31, MVT::i32);
+  DebugLoc DL = Op.getDebugLoc();
+  SDValue Res;
+
+  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
+  // to i32.
+  SDValue X = (TyX == MVT::f32) ?
+    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
+    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
+                Const1);
+  SDValue Y = (TyY == MVT::f32) ?
+    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
+    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
+                Const1);
+
+  if (HasR2) {
+    // ext  E, Y, 31, 1  ; extract bit31 of Y
+    // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
+    SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
+    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
+  } else {
+    // sll SllX, X, 1
+    // srl SrlX, SllX, 1
+    // srl SrlY, Y, 31
+    // sll SllY, SrlX, 31
+    // or  Or, SrlX, SllY
+    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
+    SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
+    SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
+    SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
+    Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
+  }
 
-// Called if the size of integer registers is not large enough to hold the whole
-// floating point number (e.g. f64 & 32-bit integer register).
-static SDValue
-LowerFCOPYSIGNSmallIntReg(SDValue Op, SelectionDAG &DAG, bool isLittle) {
-  // FIXME:
-  //  Use ext/ins instructions if target architecture is Mips32r2.
-  //  Eliminate redundant mfc1 and mtc1 instructions.
-  unsigned LoIdx = 0, HiIdx = 1;
+  if (TyX == MVT::f32)
+    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
 
-  if (!isLittle)
-    std::swap(LoIdx, HiIdx);
+  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
+                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
+  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
+}
 
-  DebugLoc dl = Op.getDebugLoc();
-  SDValue Word0 = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
-                              Op.getOperand(0),
-                              DAG.getConstant(LoIdx, MVT::i32));
-  SDValue Hi0 = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
-                            Op.getOperand(0), DAG.getConstant(HiIdx, MVT::i32));
-  SDValue Hi1 = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
-                            Op.getOperand(1), DAG.getConstant(HiIdx, MVT::i32));
-  SDValue And0 = DAG.getNode(ISD::AND, dl, MVT::i32, Hi0,
-                             DAG.getConstant(0x7fffffff, MVT::i32));
-  SDValue And1 = DAG.getNode(ISD::AND, dl, MVT::i32, Hi1,
-                             DAG.getConstant(0x80000000, MVT::i32));
-  SDValue Word1 = DAG.getNode(ISD::OR, dl, MVT::i32, And0, And1);
-
-  if (!isLittle)
-    std::swap(Word0, Word1);
-
-  return DAG.getNode(MipsISD::BuildPairF64, dl, MVT::f64, Word0, Word1);
+static SDValue LowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
+  unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
+  unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
+  EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
+  SDValue Const1 = DAG.getConstant(1, MVT::i32);
+  DebugLoc DL = Op.getDebugLoc();
+
+  // Bitcast to integer nodes.
+  SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
+  SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
+
+  if (HasR2) {
+    // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
+    // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
+    SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
+                            DAG.getConstant(WidthY - 1, MVT::i32), Const1);
+
+    if (WidthX > WidthY)
+      E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
+    else if (WidthY > WidthX)
+      E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
+
+    SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
+                            DAG.getConstant(WidthX - 1, MVT::i32), Const1, X);
+    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
+  }
+
+  // (d)sll SllX, X, 1
+  // (d)srl SrlX, SllX, 1
+  // (d)srl SrlY, Y, width(Y)-1
+  // (d)sll SllY, SrlX, width(Y)-1
+  // or     Or, SrlX, SllY
+  SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
+  SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
+  SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
+                             DAG.getConstant(WidthY - 1, MVT::i32));
+
+  if (WidthX > WidthY)
+    SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
+  else if (WidthY > WidthX)
+    SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
+
+  SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
+                             DAG.getConstant(WidthX - 1, MVT::i32));
+  SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
+  return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
 }
 
 SDValue
 MipsTargetLowering::LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
-  EVT Ty = Op.getValueType();
-
-  assert(Ty == MVT::f32 || Ty == MVT::f64);
-
-  if (Ty == MVT::f32 || HasMips64)
-    return LowerFCOPYSIGNLargeIntReg(Op, DAG);
+  if (Subtarget->hasMips64())
+    return LowerFCOPYSIGN64(Op, DAG, Subtarget->hasMips32r2());
 
-  return LowerFCOPYSIGNSmallIntReg(Op, DAG, Subtarget->isLittle());
+  return LowerFCOPYSIGN32(Op, DAG, Subtarget->hasMips32r2());
 }
 
 SDValue MipsTargetLowering::